1. Field of the Invention
This invention relates to a novel peptide present in a silkworm hemolymph wherein an antibacterial activity has been induced, an antibacterial agent comprising the peptide as an active ingredient, a novel peptide gene encoding the peptide, a novel recombinant DNA comprising the gene and a method for preparing the novel peptide.
2. Description of the Prior Art
When bacteria invade the body cavity (coelom) of an insect, an antibacterial protein or peptide is induced in a hemolymph of the insect as one of biodefense reactions. As antibacterial proteins or peptide obtainable from a silkworm hemolymph, there are known lysozyme, cecropins and the like. Lysozyme, however, exhibits an antibacterial activity against only extremely limited Gram-positive bacteria such as Micrococcus. On the other hand, cecropins exhibit an antibacterial activity against various Gram-negative and -positive bacteria, but there is a problem that they do not exhibit an effective antibacterial activity against pathogenic bacteria causing food poisoning, such as Staphylococcus aureus and Bacillus cereus.